1. Field of the Invention
This invention relates to an abrasion device suitable for abrading a surface of a workpiece.
2. Description of the Related Art
For abrading surfaces of a workpiece, and especially curved surfaces such as found on a propeller for marine vessels, a flap wheel comprising a pulley and a plurality of sandpaper or abrasive cloth bands supported on and radially outwardly extending about the periphery of the pulley has generally been used. In such an abrasion device, by rotation of the flap wheel, the sandpaper abrasive bands are brought into moving contact with the curved surfaces of the workpiece to effect abrasion finishing or shaping of same.
Since only the tip portions of the sandpaper bands are brought into contact with the surface to be treated, these portions soon wear over time, so that the effective diameter of the flap wheel is gradually reduced. Thus, it becomes necessary to control the distance between the flap wheel and the workpiece as the effective diameter changes.
Further, as the end portions of the sandpaper bands wear, the bands must be replaced frequently even through the remainder of each band is still usable. This is not only economically disadvantageous but also lowers work efficiency.